From the "Why the heck wasn't this available ages ago" department: Twitter's closed caption toggle is ??? ?? ?? ???now live on the company's iOS and Android apps.

Twitter started testing the closed captions toggle, showing up as a little "CC" button on a video with available captions, back in April.

This Tweet is currently unavailable. It might be loading or has been removed.

Now, the toggle is available for everyone.

Note that the feature was already available on the web, but now it's also there on iOS and Android.

The toggle is persistent, meaning that when you use the "CC" button to turn on captions on one video, they'll stay on for other videos in your timeline if they have captions available.

• The one Twitter setting you should turn on right now for peace of mind
• Twitter has released a browser game about its privacy settings
• How to use Twitter's new and improved alt text tools
• 4 ways mobile apps could be a lot more accessible

Prior to this, captions would show depending on several factors, such as whether you've turned on closed captioning in the accessibility settings on your Android or iOS device, and whether your device's sound was turned off.